1. Field of the the Invention
The invention relates to thermosetting resinous coating compositions, particularly to elastomeric coating compositions,and more particularly, to high solids elastomeric coating compositions.
2. Brief Description of the Prior Art
Elastomeric coating compositions are those which have excellent flexibility, particularly at low temperature, along with good hardness and durability. Such coating compositions are particularly useful on elastomeric parts of automobiles and trucks such as bumpers, front end hood sections and the side moldings.
Examples of elastomeric coating compositions are shown in U.S. Pat. No. 3,962,522. These coating compositions are based on polyesterurethane polyols cured with aminoplast. Another example of an elastomeric coating composition is that disclosed in U.S. Pat. No. 4,154,891. These coating compositions are based on polymeric polyols such as soft polyurethane polyols cured with a stoichiometric excess of an aminoplast curing agent.
U.K. Pat. No. 1,477,008 discloses coating compositions comprising thermosetting resins, for example, hard polyester polyols, soft polyurethane polyols and aminoplast curing agents.
The coating compositions of the aforementioned patents are not high resin solids type, that is, they are not sprayable at high resin solids content. This is a disadvantage in that more coating applications are required to get the desired coating thickness and appearance. Also, future air pollution standards will require a reduction of organic solvent emissions of today's organic solvent-based coating compositions. Therefore, the coating compositions described in the aforementioned patents may not be environmentally acceptable in the future.